We have been getting used to Brea getting scratchier and scratchier as the day progresses. Fortunately, she didn't follow this pattern tonight. Instead she actually starting smiling and laughing and being much more like herself. She started singing and reciting nursery rhymes and books, etc. She has also started eating a lot more.
The lactate levels are still causing us some bother. I never did find out what the lab reported the lactate value to be, but her levels were all over the place all day. They would decrease as they wanted and then suddenly jump back to the level where we all started. The cardiologists came and did an echo to look at her heart function and concluded it looks "pretty good". So the current theory is that the high lactate values are caused by dehydration. So they have given her some IV fluids. The plan (which of course is likely to change) it to keep a track of the lactate values through the night and try and take her off the heart medication in the morning again and see what happens. As far as I can tell, we will remain in the ICU until they are happy with her lactate values.